Apparatus for the manufacture of artificial filaments or fibers



M y 1934- R. H. PARKINSON El AL 3 APPARATUS FOR THE MANUFACTURE OF ARTIFICIAL FILAMENTS OR FIBERS Filed D60. 24, 1929 MATT SURFACE REGINALD H. PARKINSON FRANK A. REESON INVENTUH:

Patented May 15, 1934 APPARATUS FOR THE MANUFACTURE OF ARTIFICIAL FILAMENTS OR FIBERS Reginald Henry Parkinson and Frank Alfred Rceson, Spondon, near Derby, England, assignors to Ceianese Corporation of America, a corporation of Delaware Application December 24, 1929, Serial No. 416,272 In Great Britain January '7, 1929 3 Claims.

This invention relates to apparatus for the manufacture of artificial filaments or fibers, and more particularly for the manufacture of such filaments or fibers by the dry or evaporative method, i. e., by the extrusion of spinning solutions comprising a volatile solvent through jets or nozzles into an evaporative atmosphere which effects the removal of the volatile solvent from the extruded filaments.

According to the invention, the part of a spinning jet or nozzle which is exposed to the evaporative medium is formed or provided around the or each spinning orifice with a matt surface. Thus, in the case of multi-filament disc-type jets or nozzles, i. e., jets or nozzles having a number of spinning orifices in a disc-like member, the Whole or substantially the whole of the surface of the disc may be matt or unpolished, all the spinning orifices lying within the matt or unpolished area. The area surrounding the orifices in other types of jets or nozzles may according to the invention have a matt surfaces, and the orifices of single orifice jets or nozzles may be surrounded by a similar surface.

In the accompanying drawing, in which like reference numerals refer to similar parts in the various figures,

Figure 1 is a vertical section through the jet; and

Figure 2 is a perspective View of the jet shown in Figure 1.

The jet shown consists of a dished member 3 having a flange 4. Spinning orifices 5 are formed by perforating the base 6 of the dish 3, the drawing showing a circle of such orifices. The outer face 7 is given a matt surface by any of the methods herein indicated, this matt surface being indicated conventionally by double cross-hatching in Fig. 2.

By the employment of jets or nozzles according to the invention, increased stability of spinning is obtained, and drawing-down of the filaments, i. e. reduction of filament denier by drawing the filaments from the jet or nozzle at a speed greater 0 than the speed of extrusion, is facilitated. Ap-

parently, the rate of transfer of heat from the evaporative medium into which the filaments are spun to the spinning solution in the jets or nozzles is increased to some extent when the jets or nozzles are formed with matt surfaces. The jets or nozzles are useful in the dry-spinning of solutions of cellulose acetate or other cellulose derivatives.

The matt surface may be formed on the material of the jet or nozzle at any suitable stage of its manufacture, and either before or after the provision of the spinning orifice or orifices in the jet or nozzle. Thus, disc-type nozzles of the character above referred to may be formed from sheet material having the requisite surface, or the material of the disc may be treated to give it the matt surface prior to or after the formation of the orifices.

Various methods of surfacing the material of the jet or nozzle may be resorted to, sand blasting or etching having been found particularly suitable. For example, the jets or nozzles, or the material from which they are made may be etched with suitable acids or acid mixtures.

The following is a method which may be used for the treatment of jets or nozzles made of steel, for example, single or multi-filament disc-type nozzles of this description is given by way of example only steel, but it is to be understood that and is in no Way limitative.

The side of the nozzle disc which in use is remote from the spinning atmosphere is rubbed with tallow or other suitable grease or wax until each of the spinning apertures is or are filled. The other side of the nozzle is freed from all traces of grease and is then treated for 30 seconds with an acid mixture comprising hydrochloric acid, 5% nitric acid and 45% water, the acid What we claim and desire to secure by Letters Patent is:

1. A spinning jet for the manufacture of artificial filaments by the evaporative method characterized in that the part of the jet which is exposed to the evaporative medium is provided around each spinning orifice with a matt surface.

2. A disc-type spinning jet for the manufacture of artificial filaments by the evaporative method characterized in that the part of the jet which is exposed to the evaporative medium is provided around each spinning orifice with a matt surface.

3. In the manufacture of spinning jets for the production of artificial filaments by the evaporative method, the step of imparting a matt surface around each spinning orifice to that part of the jet which is to be exposed to the evaporative medium.

REGINALD HENRY PARKINSON. FRANK ALFRED REESON. 

